Control mechanism



Oct. 22, 1929. E. LOF 1,732,651

CONTROL MEGHANI SM Filed June 27, 1928 a Sheets-Shet 1 0a. 22, 1929. 5y L5,,- 1,732,651

CONTROL MECHANI SM Filed June 27, 1928 5 Sheets-Sheet 2 E. LOF

CONTROL MECHANISM Oct. 22, 1929.

Filed June 27, 1928 3 Sheets-Sheet 3 Patented Oct. 22, 1929 EMIL 1161?, OF STOGKHOLM, SWEDEN CONTROL MECHANISM App1ieation filed June 27, 1928, Serial No. 288,771, and in Sweden June 4, 1928.

This invention relates to that type of control mechanisms which is used to adjust machine-parts or other members in definite positions by means of a control or hand lever and 5 in which means are provided to lock the said machine-part or member in adjusted position.

The object of the invention is to provide a control mechanism of said type which is as easy to operate as that well-known type of control. mechanisms in which not the adjusted member itself but the control or hand lever is locked in its position by means of a catch and its associated handle that may be grasped by the same hand grasping the control or hand lever.

The invention is characterized, chiefly, by the fact that the connection between the de vice to lock the adjusted member and a releasing rod with its handle mounted on the control or hand lever comprises an areshaped guide and a roller or the likecooperating with said guide, one of said elements, viz the guide or the roller, being connected with the releasing rod to move therewith, while the other element is connected to the locking device, said guide being so designed that, after the releasing rod has been oper ated to release the locking device, said guide will be concentric with the centre of rotation of the control or hand lever so as to allow said lever to be then freely moved to adjust the member without affecting the locking device.

In the accompanying drawing one embodiment of the invention is illustrated. Fig. 1 is a side elevation of a control mechanism according to the invention. Fig. 2 is a plan vie thereof. Fig. 3 is a side elevation of the control lever on a larger scale, as seen from the left in Fig. 1. Fig. 4 is a horizontal section of the locking device on a larger scale.

l i ith reference to the drawings, the numeral 1 indicates the stationary table of a circular saw for edging boards, and 2 is the travelling table thereof. The movement of the travelling table 2 relatively to the stationary table is effected by means of a pair of lovers 3, 3 pivoted to the table 2 which are secured to a horizontal shaft 4. Said shaft 4: is connected by the bevel gear 5 to a control or hand lever 7 by means of which the shaft 4.

with the lovers 3 may be rotated in the one direction or the other to move the table 2 towards or away from the stationary table 1.

In order to maintainthe travelling table 2 in the position desired there is provided a locking device comprising, for instance, a toothed racli8 connected to the table 2 which extends parallel to the direction of movement of said tablesaid rack being guided in an externally threaded sleeve 9 engaging a frame 10. Guided in a lateral projection of the sleeve 9 is a catch block 12 having one tooth 13 (or more) to engage the toothed rack 8. A spring 14; serves normally to maintain the catch block 12 in engaged position. Secured to the catch block 12 is a rod 15 projecting to theside of the control or hand lever where it is pivoted to one arm of a bell crank lever 16 the other arm of which carries a roller 17. Sald roller bears against an arc-shaped bar 18 secured to a sliding block 20 movable along a guide 19 secured to the hand lever 7.

By means of a rod .21 slidably mounted on the hand lever the sliding block 20 is connected to a bell crank lever mounted at the upper end of the hand lever, the one arm of sliding block 20 and the bar 18 are displaced upwardly. The bar 18, when thus displaced, causes by means of the roller 17 the lever 16 to turn so as to move the rod 15 to the left, Fig. 1, thereby bringing the catch block 12 out of engagement with the toothed rack S.

The travelling table 2 is now free to be displaced.

The shape of the curved bar 18 is so chosen that thebar, when in its raised position above referred to, will be concentric with the/centre of rotation 6 of the hand lever 7. The hand lever may, as a result, be operated to adjust the table 2 without causing the bar18 to effect any movement of the bell crank lever 16.

It is thus seen that the locking device is in no way influenced by the movement of the hand lever. The adjustment may be read OK on a stationary scale 25 by means of a .01 a device to directly lock said operated member in adjusted position, a spring operated sliding rod with its associated handle mounted on said lever, and connections between said sliding rod and said locking device comprising an arc-shaped cam substantially concentric with the centre of said lever and a roller to engage said cam, one of said elements being connected with the locking device and the other with the sliding rod, so that upon the movement of said rod in one direction along the lever the element carried by the rod will be caused to operate the other element to release the locking device.

2. In an operating and locking mechanism the combination with an operating lever and its operative connection with the member to be operated upon the movement of the lever, of a device to directly lock said operated member in adjusted position, va spring oper ated sliding rodwith its associated handle mounted on said'lever, a guide-way rigid to said lever, a sliding block connected to the rod in engagement with said guide-Wa an arc-shaped cam rigid to said sliding lock which is substantially concentric to the centre of the lever, a lever connected to said locking device, a roller on said lever to engage said cam so as to cause the lever to swing, thereby to release the locking device upon the movement of the sliding rod with the cam in one direction.

3. In an operating and locking mechanism the combination with an operating lever and its operative connection with the member to be operated upon the movement of the lever, of a spring catch to directly cooperate with said operated member to lock same in adj usted position, a spring operated sliding rod with its associated handle mounted on said lover, a guideway rigid to said lever, a sliding block connected to the rod in engagement with said guide-way, an arc shaped cam rigid to said sliding block which is substantially concentric to the centre of the lever, a bell crank lever, connectedwith one of its arms to said spring catch, a roller on the other arm of said bell crank lever to engage said cam so as to cause the lever to swing, thereby to release the catch upon the movement of the sliding rod with the cam in the direction away from the centre of the operating lever.

In testimony whereof I have signed my name.

EMIL LOF. 

